Rock drill



Nov. 13, 1928. 1,691,570

I c. c. HANSEN I ROCK DRILL Filed June 7, 1926 INVENTOR I 9% k (an/ea aflirmen BY f\ i; a w g HIS ATTOR Y Patented Nov. 13, 1928 CHARLES C. HANSEN, OF'EASTON, PENNSYLVANIA, ASSIGNOB 'IOIINGERSOLL-R AND PA oF -icis.

COMPANY, OF JERSEY CITY, NEW- JERSEY, A CORPORATION NEW'J'ERSEY.

BOOK DRILL.

Application filed June 7 This inventionrelates to rock. drills, but.

moreparticularly to a blowing device for fluid actuated rock drills of the hammer.

The invention consists: of the combination of elements and features of construction substantially as hereinafter describedand more particularly pointed out in the appended: claim and illustrated in the accom panying drawings, in which 7 v Figure l is a longitudinalyiew, in section showing the piston in position for admitting pressure fluid to the drill. steel, .and

Figure 2 is a. View similar to Figure; 1 illustrating the manner in which. the supply of pressure fluid to the drill steelis cut off by the piston extension. v

Jrieferring to the drawings, the invention is shown embodied in a-rock drill having a cylinder A closed at. its rearward'end by a back cylinder washer B and at itsforwardend by a bushing. C. Disposed within the cylinder A is a reciprocator'y piston D adapted to deliver blowson a. hollow drill steetE supported. by a front head F'which, in the present instance, extends with its rearward end' intothe front end: of the cylinder A, The front head may be heldin assembled? position with. respect to the cylinder by means of the usual side bolts (not shown).

Disposed within the front end. of the front head F is a chuck jaw G'havi'ngthe usual flats H to engage wings J of the drill steel" Efor preventing relative rotation between the drill. steel and the chuck jaw. At the rearward end of the chuck jaw G are formed clutch teeth K to interlock with similar clutch teeth L of a chuck O. A chuck nut P is screwed into the rearward end of the chuck O and is provided with suitable ribs Q which engage slidably flutes R formed in the front end of an extension S of the piston D. I The flutes R preferably extend only along the forward end of the. extension S and are of such length with respect to the total length of the extension S that the rearward and of said flutes will not be drawn 1926. Serial No. 114 232.

into communication with the front end of;

the cylinder-when the. piston D" reaches its rearwardlimiting position during the normal operationofthe drill. By-thus'fo'rming the fliites R only on the front end of the extension S, the rearwardportion T of: the

extension will be' of smooth and. cylindrical form to cooperate slidably'with a bore Uof' the bushin C.

As will" ,e noted fromthe'foregoingd-e:

V scription, the piston D, the chuck parts in the front head F, and. thedrill steel. E are interlocked against relative rotation so that on' the rearward stroke-0f the piston D; during which stroke the piston; is adapted to rotate on the rifle bar 'V ina well understood manner the position ofthe. drill steel E will be changed in the drill holefor the succeed inglblow of the piston.

Secured to the cylinder A is a valve chest \V' having avalve chamber wherein is arranged an oscillatory. plate valve Y. The valve Y and the valve chest 'W are merely shown for illustrative purposes and it, is to be. understood that the invention is applicable to othentypes of drills in whichother types of distributing valves may be employed for distributingthe pressure fluid or, to the type of drills in which the piston acts as ameans for distributing the pressure fluid.

Passages Z and b lead'from the chamber 'X' to the rearward and front ends ofthe cylinder and are'controlled by the ends of the valve Y to admit pressure fluid tothe cylinder for reciprocating-the pistoni- A port 0 formed in the wall of" the cylinder-A serves as a free exhaust port, for the cylinder and is; controlled only by the piston D;

Pressure fluid for actuating the drill is conveyed from a source of' supply by a connection d, in this instance secured to the rearward end of the valve chest' V. The admission of pressure fluid tothe drill is controlled by. a suitable throttle'val'vee"interposed between the connection (Z and an annular chamber f adjacent to and forming a part of the valve chamber X. 7

Usually in drills of this type, means are provided for'conveying cleansing .fluid to the drill hole for removing the cuttings therefrom. Such means may consist of a tube or tubes extending through the rifle bar and the piston to deliver the cleansing fluid to the hollow drill steel E. These tubes are usually connected to a source of supply sdthat a constant flow of either pres-- sure fluid. or water, or both water and'pr'essure fluid, are constantly flowing into the drill hole. In this way the fluids are caused to intermingle and the pressure of the water which is usually of lower value than that f is formed through the valve chest W to communicate at its forward end with a pasv sage it formed through the wall of the ,cyl-

bore U of the bushing G. The annular inder A adjacent the rearward end of the bushing C. In the rearward end of the bushing C- is formed an external annular groove y to register with the passage h, and passages 70, are formed in the bushing C to convey pressure fluid fromithe groove j to an internal annular groove 0 formed in the groove 0 is preferably so positioned in the bushing C that during a portion of the stroke of the piston D, said groove will be covered by the cylindrical portion T of the piston extension" In the present instance water tube p is arranged coaxially through the drill to extend at its front end into the drill steel E. The water tube 39 maybe connected to a source of supply in a well known manner to deliver a constant stream of waterto the drill hole.

V The operation of the device is as follows: WVhen the throttle valve e is rotated to the position shown in the drawings, pressure fluid will be admitted to the chamber 7 to actuate the valveand' the piston. Upon the admission of pressure fluid to the Chillll her: 7, a constant supply of pressure fluid will be maintained in the'passages leading from the annular chamber f to the groove 0 in the bushing G1 As the piston moves rearwardly from the position illustrated in Figure 2, the groove 0 will be uncovered by the cylindrical portion T of the extension S and pressure fluid will then pass directly from the chamber f through the flutes R of theextension S into the drill steel E and will continue to flow into the drill hole until the piston D is reversed and again approaches the front end of the cylinder when the cylindrical portion T will cover the groove 0 and thus'cut off the admission of pressure fluid to the drill steel. In this way an in termittent supply of pressure" fluid will; be admitted to the drill. steel at that period of the cycle'of operations of the drill when the piston D is removed from the drill steel and whenthe minimum pressure is exerted on the 'drill steel, "thus providing a free path for the cleansing fluid through the drill into the drill hole. Y I

The above, described inventionhas been found to'be unusually 'eflieient in operation and assures a uniform intermingling otthe cleansing fluids. Another' 'desirable' advan tage of the present invention is that by dif recting the pressure fluid through tlieflutes of the extension, any. dust or foreign matter 7 which may bedrawn "through' the chuck] parts into the interior of the drill andwhichj may collect on the forward end of the flutes, will be blowntherefrom; In this way the cooperating surfaces of the flutes and the ribs of the chuck nut P will be protected against the abrading-action of such dust and, in consequence, the parts will render service for a considerably longer period of time than willsimilar parts unprovided with this novel feature.

I claim:

I In a rock drill, the combination of a 'cylinder, a bushingin the front end of the cylinder, saidabushing having a'bore, a recipe rocatory hammer piston in the "cylinderya'n extension on the piston slidahle in tliebore, said extension having flutes in its front end and a smooth cylindricaltrearward portion, a valve chest on'the cylinder havinga valve,

chamber, apassage in the valve chest leading or from a source of supply to the valve chamber, a throttle valve controlling the passage, and a passage leading from the valve chambereto the bore constantly exposed to pressure fluid from the valve chamber during the operation,

of the drill, said passage being controlled by the cylindrical portion of the extension for obtaining an uninterruptedflcw of pressure fluid through the flutesduring a portionof both the forward and, rearward. strokes of the piston.

In testimony whereof: specification. i a Y f CHAR-LES C. HANSEN.Q

I have signed, this 

